[vsnet-grb-info 15774] GRB 141109A: AAO optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  17062
SUBJECT: GRB 141109A: AAO optical observations
DATE:    14/11/12 19:34:55 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

E. Mazaeva (IKI), R. Inasaridze (AAO), A. Volnova (IKI), Molotov (KIAM), 
A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration:

We observed the field of the Swift GRB 141109A  (D'Avanzo et al., GCN 
17037) with AS-32 (0.7m) telescope of Abastumani Observatory. 
Observations were performed under mean seeing (FWHM) of 2.4". We 
obtained several unfiltered images on Nov. 10 starting on (UT) 01:05:04. 
  At the position reported in (Covino, GCN 16932) we marginally 
detected (S/N =2) the afterglow of GRB 141109A  (Covino, GCN 16932; Xu 
et al., GCN 17040; Graham et al., GCN 17041). Preliminary photometry is 
following:

date        UT start  t-T0        Filter  Exp.    OT    OT_err
                       (mid, days)         (s)

2014-11-10  01:05:04  0.836       clear   37*120  21.7  0.4

The photometry is based on several SDSS-DR9 stars R magnitudes 
transformed from SDSS-DR9 based on Lupton transformations:

SDSS-DR9            R
J093801.18-003731.5 17.6330
J093759.83-003741.8 17.2029
J093815.45-003332.9 18.2004